Free Gases MCQs with Answers
443 Gases MCQs from Chemistry, each with the correct answer and a written explanation of why it is correct. Free and unlimited, with no account needed.
Gas behaviour is explained through the kinetic molecular theory and the relationships among pressure, volume and temperature. Work includes STP, Boyle's and Charles's laws, absolute zero, the ideal gas equation, and the distinction between ideal and real gases, especially the effects of intermolecular forces and molecular volume.
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443 questions · page 15 of 23
- A. Diffusion of gas molecules
- B. Effusion of gas molecules
- C. Volume of gas
- D. Temperatue of gas
Explanation: Diffusion is the mixing of molecules with one another. Molecules of the scent fill the spaces between air molecules and the molecules of…
Correct answer: Diffusion of gas molecules- A. 120 ms-1
- B. 300 ms-1
- C. 600 ms-1
- D. 900 ms-1
Explanation: The Clausius Kinetic Energy Equation is PV=1/3Nmc2 where c is the rms speed Because we have given values of Pressure and Density so we…
Correct answer: 300 ms-1- A. 59.43 cm
- B. 52.12 cm
- C. 34.37 cm
- D. 49.23 cm
Explanation: By understanding the GRAHAM'S LAW OF DIFFUSION and it's numerical type questions this Question is very easy to solve.
Correct answer: 59.43 cm- A. 10 seconds: He
- B. 20 seconds: O2
- C. 25 seconds: CO
- D. 35 seconds: CO2
Explanation: The key to solve this question is the understanding GRAHAM's LAW OF DIFFUSION which states that: The rate of diffusion or effusion of a…
Correct answer: 20 seconds: O2- A. 0.6 ms-1
- B. 0.3 ms-1
- C. 0.9 ms-1
- D. 3 ms-1
Explanation: This is a numerical based question so review its soultion carefully.
Correct answer: 0.6 ms-1- A. I, II & III only
- B. I, II & IV only
- C. I & II only
- D. I, II, III & IV all
Explanation: This option is correct, as explained below. Statement IV is correct because the rate of effusion is inversely proportional to square root…
Correct answer: I, II & IV only- A. Shrunk
- B. Enlarged
- C. Completely collapsed size
- D. Remain unchanged in size
Explanation: When a balloon filled with ethyne is pricked with a sharp pointed needle and quickly dropped in a tank of H2 gas under identical…
Correct answer: Enlarged- A. A is at temperature T and B at T',T', T'
- B. A is lowered to a temperature T2,T2< T while B is at T
- C. Both A and B are raised to a higher temperature
- D. Both A and B are placed at lower temperature
Explanation: For two gases A and B with molecular weights MA and MB, it is observed that at a certain temperature T1, the mean velocity of A is equal…
Correct answer: A is lowered to a temperature T2,T2< T while B is at T- A. N molecules of O2
- B. 3N molecules of O2
- C. N/2 molecules of O2
- D. N/3 molecule of O2
Explanation: The solution for this question is given below:
Correct answer: N molecules of O2- A. Two times less than a hydrogen molecule
- B. Two times that of hydrogen molecule
- C. Four times that of a hydrogen molecule
- D. The same as a hydrogen molecule
Explanation: The average kinetic energy of an atom is given as 3/2 KT. ∴ It does not depend on the mass of the atom.
Correct answer: The same as a hydrogen molecule291. At normal conditions, Dalton's law of partial pressure is not applicable to which gaseous mixture:
- A. H2 and Cl2 mixture
- B. He and N2 mixture
- C. H2 and CH4 mixture
- D. CO2 and O2 mixture
Explanation: At ordinary conditions H2 and Cl2 reacts to form HCl acid. Dalton's law of partial pressure is applies only to gasses that do not react…
Correct answer: H2 and Cl2 mixture- A. Translational motion
- B. Rotational motion
- C. Vibrational motion
- D. Rotational and vibrational motion
Explanation: A mono-atomic substance can store energy only in the form of translational motion.
Correct answer: Translational motion- A. They are highly compressible.
- B. They only have vibrational motion.
- C. Sudden expansion of gases cause cooling.
- D. They exert pressure on the walls of the vessel.
Explanation: Gases have vibrational,translational and rotational motions.
Correct answer: They only have vibrational motion.- A. Rotational K.E
- B. Translational K.E
- C. Vibrational K.E
- D. None of these
Explanation: The absolute temperature of a gas is directly proportional to the average translational kinetic energy of its molecules.This relationship…
Correct answer: Translational K.E- A. The pressure of the gas increases
- B. The kinetic energy of gas molecules increases
- C. The rate of collision increases
- D. The number of moles of the gas increases
Explanation: Increasing the temperature will increase the pressure at constant volume of gas.It will also increase kinetic energy of gases due to which…
Correct answer: The number of moles of the gas increases- A. Rapid intermolecular collisions
- B. Molecular impacts against the walls of vessel
- C. Voids between the gas molecules
- D. Ideal behaviour of gases
Explanation: The pressure of a gas is due to collisions of gas molecules against the walls of container.It is a postulate of KMT.
Correct answer: Molecular impacts against the walls of vessel- A. SO2
- B. N2
- C. O2
- D. Cl2
Explanation: The rms velocity is inversaly proportional to square root of molecular mass.So,the gas with highest molecular mass will have lowest rms…
Correct answer: Cl2- A. Two times less than a hydrogen molecule
- B. Two times that of a hydrogen molecule
- C. Four times that of a hydrogen molecule
- D. The same as a hydrogen molecule
Explanation: According to the kinetic theory of gases, the average translational kinetic energy of gas particles depends only on the absolute…
Correct answer: The same as a hydrogen molecule- A. SO2
- B. N2
- C. O2
- D. Cl2
Explanation: The root-mean-square velocity of a gas is inversely proportional to the square root of its molar mass at a constant temperature.
Correct answer: Cl2- A. C*O_{2}
- B. N_{2}
- C. H_{2}
- D. SO2
Explanation: Presence of electrons is large in sulphur dioxide and hence greater van der waals interactions .
Correct answer: SO2